Optical beam steering device

Abstract

An actuator for moving the steering mirror of an optical switch is manipulated during the operation of the switch to route light beams along selected paths through free space. Structurally, the mirror has a reflecting surface area that is characterized by a largest dimension of less than fifteen millimeters, and the actuator defines a footprint within this area. The actuator includes a flexible universal pivot that is used to mount the mirror on a base member. The actuator also includes an electronic device that controls the magnetic interaction between a magnet on the mirror and a magnet on the base to selectively move the mirror on the universal pivot for the operation of the optical switch.

What is claimed is:  
     
       1. An actuator for moving a mirror, wherein said mirror defines an x-y-z coordinate system and has a reflecting surface in an x-y plane characterized by a largest dimension of less than twenty millimeters to define an area, wherein said actuator defines a footprint within said area, and wherein said actuator comprises: 
       a base;  
       a flexible universal pivot substantially centered on said mirror for mounting said mirror on said base at a substantially constant distance therefrom;  
       a first magnetic means mounted on said base;  
       a second magnetic means attached to said mirror for establishing a magnetic interconnection between said mirror and said base; and  
       an electronic means for controlling said magnetic interconnection to selectively move said mirror on said universal pivot in rotation through an angle θ around the x-axis, and in rotation through an angle φ around the y-axis, from a first orientation relative to said base into a second orientation relative to said base.  
     
     
       2. An actuator as recited in  claim 1  wherein said second magnetic means is a substantially annular shaped permanent magnet and is centered on said universal pivot. 
     
     
       3. An actuator as recited in  claim 2  wherein said first magnetic means is electromagnetic and comprises: 
       a selectively magnetic core mounted on said base;  
       an electrical coil wound around said core; and  
       a voltage source electrically connected to said coil for sending a current through said coil to magnetize said core to control said magnetic interconnection between said mirror and said base.  
     
     
       4. An actuator as recited in  claim 2  wherein said universal pivot comprises: 
       a rigid post mounted on said base to extend therefrom; and  
       a flexible connector affixed to said post and attached to said permanent magnet to allow for movement of said mirror relative to said base with substantially no fatigue flexure for said connector.  
     
     
       5. An actuator as recited in  claim 4  wherein said first magnetic means is an electromagnetic system comprising: 
       a first coil mounted on said base and connected to said electronic means for controlling current through said first coil to move said mirror through the angle θ around the x-axis; and  
       a second coil mounted on said base and connected to said electronic means for controlling current through said second coil to move said mirror through the angle φ around the y-axis.  
     
     
       6. An actuator as recited in  claim 5  wherein the angle θ is moveable through a range of ±10°, and the angle φ is moveable through a range of ±10°. 
     
     
       7. An actuator as recited in  claim 1  wherein said area of said mirror is characterized by a dimension in a range approximately between one millimeter and twenty millimeters. 
     
     
       8. An actuator for moving a mirror, wherein said mirror defines an x-y-z coordinate system and has a reflecting surface in an x-y plane characterized by a largest dimension of less than twenty millimeters to define an area, and wherein said actuator defines a footprint within said area, and wherein said actuator comprises: 
       a mechanical means substantially centered on said mirror for mounting said mirror on a base at a substantially constant distance therefrom for pivotal movement thereon;  
       a magnetic means interconnecting said mirror with said base; and  
       an electronic means for controlling said magnetic means to selectively move said mirror relative to said base via said mechanical means in rotation through an angle θ around the x-axis, and in rotation through an angle φ around the y-axis.  
     
     
       9. An actuator as recited in  claim 8  wherein said mechanical means is a universal pivot. 
     
     
       10. An actuator as recited in  claim 9  wherein said magnetic means comprises: 
       a permanent magnet attached to said mirror, said permanent magnet creating a first magnetic field; and  
       an electromagnet mounted on said base to selectively generate a second magnetic field for interaction with said first magnetic field.  
     
     
       11. An actuator as recited in  claim 10  wherein said permanent magnet is substantially annular shaped and is centered on said universal pivot, and further wherein said universal pivot comprises: 
       a rigid post mounted on said base to extend therefrom; and  
       a flexible connector affixed to said post and attached to said permanent magnet to allow for movement of said mirror relative to said base.  
     
     
       12. An actuator as recited in  claim 10  wherein said electromagnet comprises: 
       a coil mounted on said base; and  
       a voltage source for sending a current through said coil to control said magnetic interconnection between said mirror and said base.  
     
     
       13. An actuator as recited in  claim 10  wherein said electromagnet comprises: 
       a first coil mounted on said base and connected to said electronic means for controlling current through said first coil to move said mirror through the angle θ around the x-axis in a range of ±10°; and  
       a second coil mounted on said base and connected to said electronic means for controlling current through said second coil to move said mirror through the angle φ around the y-axis in a range of ±10°.  
     
     
       14. An actuator as recited in  claim 13  wherein said area of said mirror is characterized by a dimension in a range approximately between one millimeter and twenty millimeters. 
     
     
       15. A method for manufacturing an actuator for moving a mirror, wherein said mirror defines an x-y-z coordinate system and has a reflecting surface in an x-y plane characterized by a largest dimension of less than twenty millimeters to define an area, wherein said actuator defines a footprint within said area, and wherein said method comprises the steps of: 
       attaching a permanent magnet to the mirror to establish a first magnetic field having a fixed relationship with the mirror;  
       positioning a universal pivot on a base and substantially centered on the mirror at a substantially constant distance therefrom;  
       mounting the mirror on the universal pivot with the permanent magnet centered on the universal pivot;  
       locating an electromagnet on the base to selectively generate a second magnetic field for interaction with the first magnetic field; and  
       controlling the second magnetic field of the electromagnet to selectively move the mirror relative to the base via the universal pivot in rotation through an angle θ around the x-axis, and in rotation through an angle φ around the y-axis.  
     
     
       16. A method as recited in  claim 15  wherein the positioning step comprises the steps of: 
       extending a rigid post from the base;  
       affixing a flexible connector to said post; and  
       attaching the flexible connector to the permanent magnet to allow for movement of the mirror relative to the base.  
     
     
       17. A method as recited in  claim 16  wherein the mirror defines an x-y-z coordinate system and is moveable in rotation through an angle θ around the x-axis, and is moveable in rotation through an angle φ around the y-axis, and wherein the locating step comprises the steps of: 
       mounting a first coil on the base;  
       connecting the first coil to a voltage source to control current from the voltage source through the first coil to move the mirror through the angle θ around the x-axis in a range of ±10°;  
       mounting a second coil on the base; and  
       connecting the second coil to the voltage source to control current from the voltage source through the second coil to move the mirror through the angle φ around the y-axis in a range of ±10°.